text: Vincent Uzomah, who is 50 years old and understood to be supply teacher, was attacked at Dixons Kings Academy at 08:55 BST.
  He was stabbed once in the stomach with a knife during a science lesson but is in a stable condition, police said.
  The teenager was arrested in the city centre following an extensive manhunt.
  Det Supt Simon Atkinson, from West Yorkshire Police, said the teacher was attacked in front of other students.
  "There were a number of pupils who witnessed this incident, which took place in a classroom, and they are currently liaising with specially trained officers who are obviously supporting them at this difficult time.
  "This is believed to be an isolated incident and the police are continuing inquiries to establish the facts," he said.
  It is thought Mr Uzomah had only been working at the school for four weeks.
  Police said his injuries are not life threatening and his family are at his bedside.
  Executive principal of the Dixons Academy group, Nick Weller, said: "It happened right at the beginning of the school day and there were some students who witnessed it.
  "Those students have been interviewed by the police. Obviously, it's a very shocking thing for them to see.
  "The general atmosphere in the school is very calm, quite orderly, we're trying to keep to normal routines as much as possible."
  Mr Weller said there was nothing in school that suggested the attack was about to happen.
  He added: "The police are looking into the lead up to this incident, there was nothing in school that led up to it.
  "There may have been other people outside the school who maybe knew something."
  He confirmed the suspect has been a pupil at the school for a year.
  The school, formerly called the King's Science Academy, opened in 2011 and was one of the first free schools to open.
  It has about 700 pupils and has since become part of the Dixons academy group.
  Education Secretary Nicky Morgan said violence of any kind in schools is "totally unacceptable", adding that her department is "ready and prepared to offer all necessary support".
  Ian Murch, of the National Union of Teachers' Bradford branch, which has members at the school, said: "Obviously people are shocked - they would be when an incident like this happens at a school. We hope it can be resolved without any more suffering or difficulties for anybody."
  He said the incident "does raise questions with people about safety and what can be done to improve safety".
target: A 14-year-old boy has been arrested on suspicion of attempted murder after a teacher was stabbed at a Bradford school.